The Oak Silk Moth (ヤママユガ, Yamamayuga) is a relatively rare insect found on trees during summer nights. It is notable for being very skittish, and will fly away much more willingly than other tree insects. When flying away, it makes a distinct loud flapping sound.

Upon being donated, the creature can be found in the room of the bug exhibit with the Rafflesia in, resting on a tree on the east side of the room. It can be seen better if the camera is adjusted.

"Oak silk moths are seen in the summer and are one of the largest moth species in the world. They make silk from their mouths as they transition into the pupa stage. As adults, they don't eat anything and only live off the nutrients they stored while they were caterpillars."

The hercules moth, named the oak silk moth, are among the largest moths in the world. Both their body and wings have the record, but their bodies are quite small compared to their wings. They are named after the hero of Greek Mythology. Like in game, when scared, they flee, releasing a very heavy flap. Transparent sections on the wings in some moths and butterflies help serve as a camouflage, so that predators cannot see the insect.

Atlas moths are a saturniid moth, a group that includes the famous luna moth. Despite what their common name suggests, they are only distant cousins of the domestic silk moth (Bombyx mori) which belong to the family Bombycidae.